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Interests in adsorption go back to his PhD when he studied adsorption of proteins to polymers. He did an extensive surface chemistry course at the time and did a lot of work on zeta potential of particles. Since then he has designed processes using activated carbon as well as activated clays for cleaning solvents. His experience has led him consult on a variety of projects inclding: ultra high-strength concrete, coagulating agents for minerals and, recently, mercury adsorption in natural gas pipes.

This equation is very useful. It does not have an actual derivation curiously enough, as it came from the rate equivalent of the van't Hoff equation for which there is a derivation. He has used it extensively for analyzing rate data especially accelerated stability data for biological substances where its predictions worked well. As a consultant he has examined much data on the stability of latex items (condoms and rubber gloves) and it is clear that ambitious predictions of shelf life (say 5 years) cannot be got from Arrhenius decay analysis. Having said that one should add that one needs data to be as close as possible to the molecular changes observed to enable Arrhenius analysis to work. It is also useful in understanding the thermodynamics of chemical reactions from which one gets a feeling for the activation energy and the usefulness of catalysis.

He has taught process plant design for more than 16 years to undergraduates and learned much himself in the process. At the same time he practiced what he preached and built several plants of his own design. These were on the scale of an oil refinery but pretty demanding in any case. The biggest one was a 100 tonne/day plant for wax emulsion. He designed several innovations for this plant such as a hydrocyclone wax melter and a control scheme dubbed "inverted cascade control". As well as this he knows from experience what goes into a plant design and what can go wrong, namely everything. Since then he has designed and built several smaller plants, his favorites being: (i) a direct-contact chilled brine vapour scrubber and (ii) a supercritical methanol plant for biodiesel.

He has done a lot of this mainly for clients for his consulting business. The client comes typically with a grand scheme for harvesting mineral salts or for chilling rocket fuel or for converting waste into money. More often than not after reviewing the whole scenario and doing a preliminary costing on the process he recommends that they shelve it. However there have been some ideas that get up with some innovation here and there.

He could list all the unit operations that one calls on to design processes but he won’t bother to. Let it be said that he has a pretty good grasp of them and uses them as needs be. He is not much good at Aspen or Hysis as he came in too early but when he needs to he simply uses one of his former students.

He is not a scientist but a chemical engineer who typically picks up the science as needed. So he will not rabbit on about DLVO theory and double layer theory. A more practical person, he can coagulate colloids modify their surfaces in useful ways and generally understand how they think.

This is another term for explosion if you are interested in risk analysis. He has done a lot of this including mathematical modelling of fires BLEVES etc. Management theory comes into this a bit as well. Identifying areas of risk and potential problems is something he has done since he was an undergraduate when he segregated dangereous goods in a chemical warehouse. The company were storing all the oxidants and the fuels in the one large shed, called "the bomb house" quite aptly. He moved all the fuels to one site and all the oxidants to another. Since then he has done many site visits to review safety and many mathematical models of hazardous scenarios for quantitative risk analysis as well as HAZOP studies of new plant for industry.

A micelle is an entity made from amphiphiles, molecules that have a polar end and a non-polar end such as detergents and soaps. A micelle is a cell indeed made from a collection of many amphiphile molecules. Oil in water are the common ones. He has been recently engaged in a consulting job as an expert witness for a company that supplies a propane-deasphalting process for re-refining used motor oil. In this case the micelles are water-in-oil and these are encouraged to swap phases and become oil-in-water micelles by virtue of a phase-transfer catalyst, which happens to be a surface active agent of opposite charge. The process is co-acervation where the charges were neutralized and the micelles destroyed and then rebuilt. He has also studied the effect of nonionic surfactants on enzymes finding reversible inhibition brought about by increased mass transfer resistance.

Every substance has a vapour pressure. One can use Antoine coefficients to calculate them but the real story is how material gets transported from one phase to another. Distillation, Henry's Law and Raoult's Laws are relevant topics. The supercritical state comes in as well. Some time ago he developed a model to explain the non-polar behaviour of SC substances such as water and methanol. Where did the polarity of these molecules go in the SC state he wondered. His answer was clusters of 3 or 4 monomers in which the individual polarity of each monomer was neutralized. The model was confirmed by tunneling electron microscopy several years later independently. He says he felt like Kekule when he "saw" the correct structure of the benzene molecule.

He did lots of electrophoretic mobility measurements on latex particle coated with human immune proteins such as gamma globulins. The work found bilayers of protein were adsorbed and this was a surprise because he was expecting monolayers. Several years later he attended a conference where a scholar from the Max Planck Institute gave a talk on the zeta potential of latex particle which showed him how much new information could be obtained from this technique when approached by one of the foremost research institutions in the world. He now realizes that he knows much less than he thought about zeta potential.


The expert is currently involved in reviewing the operation of a waste oil refinery for a legal case.The expert is currently reviewing problems in petroleum pipeline behavior from offshore rig.The expert designed, built and commissioned a full-scale chemical plant exported to Hong Kong.The expert reviewed the risk of dust explosion on site in a food factory.A supercritical-methanol biodiesel pilot plant was designed and built by the expert.